WO2022224624A1

WO2022224624A1 - Work machine

Info

Publication number: WO2022224624A1
Application number: PCT/JP2022/011129
Authority: WO
Inventors: 悠介鈴木; 宏明田中; 寿身中野; 靖彦金成; 博史坂本; 昭広楢▲崎▼
Original assignee: 日立建機株式会社
Priority date: 2021-04-19
Filing date: 2022-03-11
Publication date: 2022-10-27
Also published as: JP7375260B2; JPWO2022224624A1

Abstract

A hydraulic shovel 1 comprises an IMU sensor 30S that detects the posture of a turning body 4, and a main controller 34 in which the position of a boundary 60 of an operation restricted region 59 which a work device 2 is prohibited from entering is stored on a vehicle body coordinate system set for the turning body. A main controller 37 calculates an uplift angle θ of a traveling body 4 on the basis of the output from the IMU sensor 30S, calculates a rotation center Cr (Crf, Crb) around which the traveling body is uplifted on the basis of the uplift angle θ, and corrects the position of the boundary 60 on the vehicle body coordinate system on the basis of the uplift angle and the rotation center.

Description

working machine

The present invention relates to work machines used for road construction, construction work, civil engineering work, dredging work, and the like.

As a work machine used for road construction, construction work, civil engineering work, dredging work, etc., a revolving body is attached to the upper part of the traveling body that runs by the power system, and an articulated front working device is attached to the revolving body. It is known that each front member constituting the front working device is mounted so as to be vertically swingable and driven by a cylinder. An example of this is a so-called hydraulic excavator having a front working device composed of a boom, an arm, a bucket, and the like.

For this type of hydraulic excavator, for example, an operation restriction area (also called an intrusion prohibited area) for the front work equipment is set in a coordinate system (body coordinate system) based on the excavator body, and the front work equipment is set in the operation restriction area. In order to prevent the intrusion of dust, there is a device that displays the distance between the front work device and the restricted operation area on a monitor or the like to alert or warn the operator. In addition, there is also a system that restricts the operation of the front work device according to the distance between the front work device and the operation restricted area so that the front work device does not enter the operation restricted area.

Patent document 1 describes a vehicle body lower area (operation restriction area) that prohibits entry of the tip of the bucket, which is an area below the traveling body (crawler) set to prevent the collapse of the ground on which the hydraulic excavator is placed. , a technique for displaying on a monitor a boundary line between a range (workable range) that can be reached by a front working device. More specifically, when the rotating structure (vehicle body) is horizontal, the boundary line between the lower body area and the workable area is set in the vertical direction in the global coordinate system. is set so that the boundary line is maintained in the vertical direction in the global coordinate system, and when the rotating body is tilted backward, the angle between the ground surface on which the rotating body is mounted and the boundary line is 90 degrees. A controller is disclosed that corrects the boundary line as described above.

JP 2012-172427 A

By the way, hydraulic excavators are sometimes operated so that part of the traveling body is lifted while the front work device is in contact with the ground in order to fully demonstrate its work capacity. For example, when excavating hard ground and maximizing the downward excavating force of the front working equipment, the rear part of the traveling body (counterweight side) contacts the ground and the front part of the traveling body (front working device side) floats up. Operate the front working device (operate so as to be in a so-called jack-up state). On the other hand, when you want to maximize the upward lift force of the front working device, for example, when lifting a heavy load, operate the front working device so that the front part of the traveling body touches the ground and the rear part of the traveling body floats up. Focusing on the posture of the running body in both cases, in the former case, the running body rotates around the contact point (rotation center) at the rear of the running body, and in the latter case, becomes a posture that rotates around the grounding point (rotation center) of the front part of the running body. That is, the center of rotation of the running body differs depending on whether the front part or the rear part of the running body is lifted. In order to correct the display of the restricted operation area according to such a change in the posture of the traveling object, in the coordinate transformation between the vehicle body coordinate system and the gravitational coordinate system when correcting the display position of the restricted operation area, not only rotational movement but also Parallel movement (that is, movement of the center of rotation) must also be considered.

Regarding this point, the technology of Patent Document 1 assumes that both the front and rear parts of the running body are in contact with the ground (that is, it does not assume that the running body is lifted), and the lower vehicle body region When correcting the boundary line of the workable range, only rotational movement based on the front end of the crawler belt is used. Therefore, if the front or rear portion of the traveling body is lifted as described above, it cannot be dealt with, and the limited operation region cannot be maintained accurately.

The present invention has been made in view of the above problems, and its purpose is to provide a work machine that can accurately maintain the restricted operation area even when the front or rear part of the traveling body is lifted.

The present application includes a plurality of means for solving the above problems. a first attitude sensor for detecting the attitude of the revolving body; and a controller stored on a coordinate system, wherein the controller calculates a lift angle of the running body based on the output of the first attitude sensor, and lifts the running body based on the lift angle. The actual center of rotation is calculated, and the position of the boundary line in the vehicle body coordinate system is corrected based on the lifting angle and the center of rotation.

According to the present invention, even if the front or rear part of the traveling body is lifted, the operation restricted area can be accurately maintained, and the workability of the operator can be maintained satisfactorily.

1 is a side view of a hydraulic excavator that is a working machine to which an embodiment of the present invention is applied; FIG. 1 is a configuration diagram of a control system according to an embodiment of the present invention; FIG. 3 is a diagram showing the configuration (functional block diagram) of a main controller according to the embodiment of the present invention; FIG. FIG. 3 is a diagram showing a state in which the hydraulic excavator (running body) is in surface contact with the horizontal ground; Fig. 10 is a diagram showing a state in which the revolving body of the hydraulic excavator is tilted backward (a state in which the front part of the traveling body is lifted); FIG. 10 is a diagram showing a state in which the revolving body of the hydraulic excavator is tilted forward (a state in which the rear of the traveling body is lifted); FIG. 5 is a diagram showing an example of a screen on a monitor showing the positional relationship between the boundary line of the restricted operation area and the hydraulic excavator. FIG. 4 is a flow chart showing an example of the flow of calculation by each unit shown in the main controller in FIG. 3; FIG. 1 is a top view of a hydraulic excavator 1 according to this embodiment; FIG. FIG. 10 is a side view of the hydraulic excavator when the front working device side of the traveling body is lifted in the cases of A and B of FIG. 9; FIG. 10 is a diagram for classifying based on the relative angle φ which of the cases A and B in FIG. 9 corresponds. 9 is a flowchart of processing executed by a main controller according to the second embodiment;

Embodiments of the present invention will be described below with reference to the drawings.

<Target device>
As shown in FIG. 1, a hydraulic excavator (working machine) 1 according to the first embodiment of the present invention includes a traveling body 4, a revolving body 3 attached to the top thereof, and a plurality of

front members

20, 21, 22. and an articulated front working device 2 rotatably attached to a revolving body 3 .

The revolving body 3 is attached to the traveling body 4 so as to be able to revolve in the horizontal direction, and is driven to revolve by a revolving hydraulic motor (not shown).

The front working device 2 includes a boom 20 whose base end is rotatably connected to the revolving body 3, an arm 21 whose base end is rotatably connected to the tip of the boom 20, and a base end of the arm 21. A bucket 22 rotatably connected to the tip side, a boom cylinder 20A having the tip side connected to the boom 20 and the base end side connected to the revolving body 3, and the tip side connected to the arm 21 and the base end side to the boom 20. , a first link member 22B whose tip side is rotatably connected to the bucket 22, and a second link whose tip side is rotatably connected to the base end side of the first link member 22B A member 22C and a bucket cylinder 22A that spans between the connecting portion of the two

link members

22B and 22C and the arm 21 are provided. These

hydraulic cylinders

20A, 21A, and 22A are configured so as to be vertically rotatable about their connecting portions.

The boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A have a structure that can be expanded and contracted by supplying and discharging hydraulic oil discharged from the hydraulic pump 36b (see FIG. 2), and by expanding and contracting, the boom 20 , the arm 21 and the bucket 22 can be rotated (operated). The bucket 22 can be arbitrarily replaced with an attachment (not shown) such as a grapple, breaker, ripper, magnet, or the like.

The boom cylinder 20A has a pressure sensor (boom bottom pressure sensor) 20BP for detecting the pressure on the bottom side of the boom cylinder 20A and a pressure sensor (boom rod pressure sensor) 20RP for detecting the pressure on the rod side of the boom cylinder 20A. installed. These two pressure sensors 20BP and 20RP can function as load detectors for the boom cylinder 20A.

An inertial measurement unit sensor (hereinafter referred to as an IMU sensor) (boom) 20S for detecting the attitude of the boom 20 is attached to the boom 20, and an IMU sensor for detecting the attitude of the arm 21 is attached to the arm 21. (Arm) 21S is attached. An IMU sensor (bucket) 22S for detecting the posture of the bucket 22 is attached to the second link member 22C. The IMU sensor (boom) 20S, the IMU sensor (arm) 21S, and the IMU sensor (bucket) 22S are each composed of an angular velocity sensor and an acceleration sensor, and detect the inclination angle, angular velocity, and acceleration of each

front member

20, 21, 22. detection is possible. In this paper, these three

IMU sensors

20S, 21S, 22S that respectively detect the attitudes of the three

front members

20, 21, 22 are sometimes referred to as third attitude sensors.

The revolving body 3 has a main frame 31. On the main frame 31, there are an IMU sensor (revolving structure) 30S for detecting the tilt angle of the revolving structure 3, an operator's cab 32, and a plurality of hydraulic actuators in the hydraulic excavator 1. A main controller (drive control controller) 34, a prime mover 36 having an engine 36a and a hydraulic pump 36b driven by the engine 36a, and a hydraulic actuator (for example, a

hydraulic cylinder

20A, 21A, and 22A), and a weight for balancing the hydraulic excavator 1 during operation. A counterweight 37 positioned on the rear side of the revolving body 3 and a revolving motor 38 for revolving the revolving body 3 in either the left or right direction are mounted.

The IMU sensor (revolving body) 30S is composed of an acceleration sensor and an angular velocity sensor, and can detect the inclination (inclination angle) of the revolving body 3 with respect to the horizontal plane, as well as the angular velocity and acceleration. In this paper, the IMU sensor 30S that detects the attitude of the revolving body 3 may be referred to as a first attitude sensor.

The operator's cab 32 includes an operation input device 33 for inputting operations by the operator, and a device for storing in the main controller 34 the position of the boundary line of the restricted operation area into which the front work device 2 is prohibited from entering. An operation restriction area setting device 100 and a monitor (display device) 110 for displaying various information about the hydraulic excavator 1 including the position of the boundary line of the operation restriction area are provided. The boundary line of the restricted operation area can be set, for example, on a three-dimensional coordinate system (vehicle body coordinate system) set on the revolving superstructure 3 . That is, for example, a coordinate system can be set in which the height direction, the front-rear direction, and the left-right direction of the revolving body 3 are used as coordinate axes. In the example shown in FIG. 1, a tablet terminal (tablet computer) having a touch panel is used as a device that doubles as the operation restriction area setting device 100 and the monitor 110. In this connection, two codes 100 are used for one symbol. , 110 are labeled. As the operation restricted area setting device 100, a controller including an input device (a computer including a memory and a processor) may be used instead of the tablet terminal.

The operation input device 33 includes two operation levers 33a (illustrated) for instructing the rotation of the front work device 2 (boom 20, arm 21, bucket 22) and the rotation of the revolving body 3 according to the operator's operation. are combined into one), and two travel control levers 33c (illustrated are combined into one) for instructing the running operation of the left and right crawler belts 45 related to the traveling body 4 according to the operator's operation. , and a plurality of operation sensors 33b (collected as one sensor in the drawing) for detecting the amount (operation amount) of each operation lever 33a, 33c pushed down. A plurality of operation sensors 33b detects the amount by which the operator pushes down each of the four operation levers 33a and 33c, thereby detecting the motions requested by the operator to the

front members

20, 21, 22, the revolving body 3, and the traveling body 4. The speed is converted into an electric signal (operation signal) and output to the main controller 34 . The operation input device 33 (operating levers 33a and 33b) may be of a hydraulic pilot type that outputs hydraulic oil whose pressure is adjusted according to the amount of operation as an operation signal. In that case, a pressure sensor is used as the operation sensor 33b, and a signal detected by the pressure sensor is output to the main controller 34 to detect the amount of operation.

The hydraulic control device 35 includes a plurality of electromagnetic control valves 35a that generate hydraulic oil (pilot pressure) at a pressure corresponding to an operation command value (command current) output from the main controller 34, and output from the corresponding electromagnetic control valves 35a. It is driven by hydraulic oil (pilot pressure) applied to the hydraulic excavator 1, and is composed of a plurality of direction switching valves 35b for controlling the flow rate and flow direction of the hydraulic oil supplied to the plurality of hydraulic actuators mounted on the hydraulic excavator 1, respectively. The operation command value output from the controller 34 is generated based on the operator's operation input to the operation levers 33a and 33b. Operation command values (including stop command values) for non-existent hydraulic actuators may also be generated. When an operation command value is output from the main controller 34 to the electromagnetic control valve 35a, the corresponding direction switching valve 35b is operated, and the hydraulic actuator (for example, the

hydraulic cylinders

20A, 21A, 22A) corresponding to the direction switching valve 35b is operated. ) works. Hydraulic actuators may include those that drive attachments and equipment not included above.

The prime mover 36 comprises an engine (prime mover) 36a and at least one hydraulic pump 36b driven by the engine 36a. 38 is supplied with pressure oil (hydraulic oil) necessary for driving the . The driving device 36 is not limited to this configuration, and other power sources such as an electric pump may be used.

The turning angle sensor 40S is a sensor (second posture sensor) that detects the relative angle φ between the turning body 3 and the traveling body 4, and is mounted on the hydraulic excavator 1 so as to detect the relative angle φ. A potentiometer can preferably be used as the turning angle sensor 40S.

The traveling body 4 includes a track frame 40 , left and right crawler belts 45 attached to the track frame 40 , and left and right traveling motors 41 for driving the left and right crawler belts 45 so as to rotate the track frame 40 . there is The operator can make the hydraulic excavator 1 travel by adjusting the rotation speed of the left and right travel hydraulic motors (hydraulic actuators) 41 by appropriately operating the two travel control levers 33c. The running body 4 is not limited to one having crawler belts 45, and may be one having running wheels or legs (outriggers).

<System configuration>
FIG. 2 is a system configuration diagram of a hydraulic control system mounted on the hydraulic excavator 1 of this embodiment. It should be noted that the description of the parts that have already been described above may be omitted as appropriate.

As shown in this figure, the main controller 34 includes an operation restricted area setting device 100, a monitor 110, a plurality of operation sensors 33b, an IMU sensor 30S (first attitude sensor), a plurality of

IMU sensors

20S, 21S, 22S (third attitude sensor), turning angle sensor 40S (second attitude sensor), multiple pressure sensors 20BP and 20RP (load detectors), and multiple electromagnetic control valves 35a are electrically connected, It is configured to be able to communicate with these.

The operation restricted area setting device 100 outputs the position data of the boundary of the operation restricted area set by the operator to the main controller 34 . The boundary of the limited operation area can be set, for example, in the vehicle body coordinate system set in the revolving superstructure 3 . The position data of the boundary of the restricted operation area may be directly input by the operator via the restricted operation area setting device 100, or the design data created in advance on the geographical coordinate system, the site coordinate system, etc. may be used. Via the restricted area setting device 100, coordinate transformation may be added as appropriate and input may be performed. As shown in FIG. 4 , the restricted operation area 59 can be set at any position with respect to the excavator 1 . Also, the shape of the operation restriction area 59 may be a polygon or a curve.

It should be noted that the operation restriction area setting device 100 only needs to have a function of storing the position data of the boundary of the preset operation restriction area 59, and can be replaced by a storage device such as a semiconductor memory. Therefore, if the position data of the boundary of the restricted operation area 59 is stored in, for example, a storage device within the main controller 34 or a storage device mounted on the hydraulic excavator, it can be omitted.

The monitor 110 monitors the position of the boundary of the restricted operation area 59, the attitude of the hydraulic excavator 1 (including the attitudes of the front working device 2 and the bucket 22), the distance and positional relationship between the boundary of the restricted operation area 59 and the bucket 22, and the like. information to the operator.

The main controller 34 is a controller in charge of various controls related to the hydraulic excavator 1 . There are two characteristic controls that can be executed by the main controller 34 of this embodiment.

First, the main controller 34 controls the operation of the front work device 2 beyond the intersection line 60 (referred to as the boundary line 60) between the operation plane of the front work device 2 and the boundary of the operation restriction area 59 (see FIG. 4). The target speed vector of the front work device 2 so as not to enter the area 59 (for example, the target speed vector is calculated so as to decrease as the distance between the front work device 2 and the boundary line 60 decreases, and when the distance is zero) , zero is calculated as the target speed vector), and the hydraulic pressure of at least one of the plurality of

hydraulic cylinders

20A, 21A, 22A is adjusted so that the front working device 2 operates according to the calculated target speed vector. Region limit control can be executed by calculating and outputting operation command values for controlling the cylinders. That is, according to this area restriction control, for example, even if the operator inputs an arm cloud operation while the front work device 2 is positioned near the operation restriction area 59, the front work apparatus 2 continues outside the operation restriction area 59. Since the front working device 2 is semi-automatically controlled so as to be positioned at the front working device 2 (for example, the front working device 2 semi-automatically stops when it approaches the operation restriction area 59), the front working device 2 can be reliably prevented from entering the operation restricted area 59.

Secondly, the main controller 34 calculates a lifting angle θ (details will be described later) of the running body 4 based on the output of the IMU sensor 30S of the revolving body 3, and based on the lifting angle θ, the moving body 4 rises. A rotation center Cr (details will be described later) can be calculated, and the position data of the boundary line in the vehicle body coordinate system can be corrected based on the calculated lifting angle θ and the rotation center Cr. As a result, when the position of the boundary line 60 is set on the vehicle body coordinate system, it is possible to prevent the region restriction control from being executed along the erroneous boundary line even when the traveling body 4 is lifted.

The operating plane of the front working device 2 is the plane on which the

front members

20, 21, 22 operate, that is, the plane orthogonal to all the three

front members

20, 21, 22. Among them, for example, a plane passing through the center in the width direction of the front working device 2 (the center in the axial direction of the boom pin serving as the rotation axis on the base end side of the boom 20) can be selected.

<Operation input device>
In general, hydraulic excavators are set so that the larger the amount of tilting of the operating levers 33a and 33c (tilting amount), the faster the operating speed of each of the

hydraulic actuators

20A, 21A, 22A, 38 and 41. By changing the amount of tilting the levers 33a, 33c, the operating speed of each

hydraulic actuator

20A, 21A, 22A, 38, 41 is changed to operate the hydraulic excavator 1.

The operation sensor 33b electrically detects the operation amount (tilt amount) of the operation lever 33a with respect to the boom 20, arm 21, bucket 22 (boom cylinder 20A, arm cylinder 21A, bucket cylinder 22A) and swing body 3 (swing motor 38). The operation speed of the boom cylinder 20A, the arm cylinder 21A, the bucket cylinder 22A, and the swing body 3 requested by the operator can be detected based on the detection signal of the operation sensor 33b. . Further, the operation sensor 33b includes a sensor that electrically detects the operation amount (tilt amount) of the operation lever 33c with respect to the traveling motor 41. Based on the detection signal of the operation sensor 33b, the operator makes a request. The operating speed of the running body 4 can be detected. The operation sensor is not limited to the one that directly detects the amount by which the operation levers 33a and 33c are tilted, but it is a method that detects the hydraulic oil pressure (operation pilot pressure) output by the operation of the operation levers 33a and 33c. may

<Attitude sensor>
The IMU sensor (rotating body) 30S, IMU sensor (boom) 20S, IMU sensor (arm) 21S, and IMU sensor (bucket) 22S can function as an angular velocity sensor, an acceleration sensor, and an inclination angle sensor, respectively. Angular velocity, acceleration data, and tilt angle data at each installation position can be obtained from these IMU sensors. The boom 20, the arm 21, the bucket 22, the boom cylinder 20A, the arm cylinder 21A, the bucket cylinder 22A, the first link member 22B, the second link member 22C, and the revolving body 3 are mounted so as to be able to rotate (revolve). Therefore, the attitudes and positions of the boom 20, the arm 21, the bucket 22, and the revolving body 3 in the vehicle body coordinate system can be calculated from the dimensions of each part and the mechanical link relationship. The posture and position detection method shown here is just an example, and a method that directly measures the relative angle of each part of the front work device 2, or a method that detects the strokes of the boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A. The posture and position of each part of the hydraulic excavator 1 may be calculated.
<Load detector>
The pressure sensors 20BP and 20RP, which are load detection devices, may be directly attached to the boom cylinder 20A as described above, or may be attached on the oil passage from the hydraulic control device 35 to the boom cylinder 20A. Moreover, the load detection device is not limited to the pressure sensors 20BP and 20RP, but may be a load cell that directly detects the torque acting on the connecting portion between the boom 20 and the revolving structure 3, or detects the strain of the front working device 2 to detect the load. An estimation method (strain gauge) may be used.

<Main controller>
FIG. 3 is a configuration diagram of the main controller 34. As shown in FIG. The main controller 34 includes, for example, a CPU (Central Processing Unit) (not shown), a storage device such as a ROM (Read Only Memory) or an HDD (Hard Disc Drive) that stores various programs for executing processing by the CPU, and the CPU. It is configured using hardware including a RAM (Random Access Memory) that serves as a work area when executing a program. By executing the programs stored in the storage device in this manner, the attitude calculation unit 710, the operation restriction area calculation unit 720, the operation restriction area correction unit 730, the floating judgment unit 910, the floating angle computing unit 920, the floating center computing unit 930, functions as the operation command unit 310; Next, the details of the processing performed by each unit will be described.

<Posture calculation unit 710>
The posture calculation unit 710 detects acceleration signals and angular velocity signals obtained from the IMU sensor (boom) 20S, IMU sensor (arm) 21S, IMU sensor (bucket) 22S, and IMU sensor (rotating body) 30S, 21, the bucket 22, and the revolving body 3 (inclination angle) are calculated. If the dimensions of the

front members

20, 21, and 22 are added to the result of calculation of the posture, the position of the front working device 2 can also be calculated. The position of the front working device 2 in the vehicle body coordinate system can be calculated from the attitudes of the boom 20, arm 21 and bucket 22 that can be calculated from three

IMU sensors

20S, 21S, 22S (third attitude sensors).

<Operation restriction area calculation unit 720>
The operation restriction area calculation unit 720 calculates the position of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system based on the position data of the operation restriction area 59 input from the operation restriction area setting device 100 . The position of the boundary line 60 calculated here is the position of the boundary line 60 when the revolving superstructure 3 is horizontal, and is hereinafter sometimes referred to as the "initial position".

<Floating Determination Unit 910>
A lift determination unit 910 determines whether or not a part of the traveling body 4 is lifted. 4 shows a state in which the running body 4 is in surface contact with the horizontal ground, FIG. 5 shows a state in which the revolving body 3 is tilted backward (a state in which the front of the running body 4 is lifted), and FIG. indicates a state in which the revolving body 3 is tilted forward (a state in which the rear of the running body 4 is lifted).

When the traveling object 4 is lifted, the boundary line 60 of the operation restriction area 59 is corrected. is not corrected (that is, the position of the boundary line 60 is kept at its initial position). That is, whether or not the traveling body 4 is lifted coincides with whether or not the boundary line 60 of the operation restriction area 59 is corrected.

A method for judging whether the traveling body 4 has risen will be explained. If the hydraulic excavator 1 receives a large reaction force from the ground via the front work device 2 while the working machine 1 is stopped from traveling by the traveling body 4, the traveling body 4 may be lifted.

Therefore, the lift determination unit 910 of the present embodiment monitors the presence or absence of an operation input to the travel control lever 33c (that is, the presence or absence of travel) by the output of the operation sensor 33b, and detects the presence or absence of the lift of the traveling body 4 by the IMU sensor (turning motion). body) Monitor the output of 30S. When the output of the IMU sensor (revolving body) 30S changes while the traveling control lever 33c is not operated (that is, in the non-running state), the floating determination section 910 determines that the traveling body 4 is floating. On the other hand, if the travel control lever 33c is steered, or if the output of the IMU sensor (revolving body) 30S is constant, it is determined that the travel body 4 is not lifted.

As another determination method, the load of the front working device 2 is detected, and if the inclination angle of the traveling body 4 changes while the reaction force required for the traveling body 4 to float up is obtained, the traveling body 4 may be determined to be floating. For example, in the uplift determination unit 910, the thrust F1 of the boom cylinder 20A is calculated from outputs of two pressure sensors (rod side, bottom side) 20BP and 20RP related to the boom cylinder 20A. By comparing the calculated thrust force F1 of the boom cylinder 20A with the thrust force F2 of the boom cylinder 20A required to support the front working device 2, it is determined whether or not the reaction force necessary for lifting the traveling body 4 is obtained. and determine whether or not there is floating. Specifically, (1) when the thrust F1 of the boom cylinder 20A is different from the thrust F2 required to support the front working device 2, and when the output of the IMU sensor (revolving body) 30 changes, the traveling body 4 is determined to be floating. On the other hand, (2) when the thrust force F1 of the boom cylinder 20A matches the thrust force F2 required to support the front working device 2, or when the output of the IMU sensor (rotating body) 30S is constant (more specifically, can be regarded as constant), it is determined that the running body 4 is not floating (the running body 4 is in surface contact with the ground).

By using this method, it is possible to determine whether the revolving structure 3 is tilted forward or tilted backward due to the lifting of the traveling structure 4 . If F1<F2 holds true in the above case (1), it indicates that the revolving body 3 is tilted backward, and the rear side of the revolving body 3 (the side of the counterweight 37) contacts the running body 4 with the ground. It can be determined that the traveling body 4 is floating around the line (see FIG. 5). Conversely, if F1>F2 holds, it indicates that the revolving body 3 is tilted forward, and the traveling body 4 travels around the contact line where the traveling body 4 contacts the ground on the front side of the revolving body 3 (on the side of the front working device 2). It can be determined that the body 4 is floating (see FIG. 6).

It should be noted that the "thrust force F2 of the boom cylinder 20A required to support the front work device 2" used in the above comparison is the attitude of each

front member

20, 21, 22 calculated by the attitude calculation unit 710, and the It can be calculated based on the weights of the

front members

20, 21 and 22, and can be calculated by general dynamic calculation.

<Lifting Angle Calculator 920>
A lifting angle calculator 920 calculates a change θ in the inclination angle of the revolving body 3 due to the lifting of the traveling body 4 based on the output of the IMU sensor (revolving body) 30S. Here, this angle θ is referred to as a lift angle.

A method of calculating the rising angle θ of the traveling body 4 will be explained. As shown in FIGS. 5 and 6, the running body 4 floats on the side of the front working device 2 or on the side of the counterweight 37 depending on the working conditions. The rising angle θ is defined by the angle between the ground surface with which the running body 4 is in contact and the bottom surface of the running body 4 . That is, by calculating the deviation between the tilt angle immediately before the running body 4 lifts up (the tilt angle of the ground that the running body 4 is in contact with) and the tilt angle after lifting, the following equation (1) is obtained. Angle θ can be calculated. Since the hydraulic excavator 1 has a structure in which the revolving structure 3 and the traveling structure 4 rotate about one axis, the inclination of the traveling structure 4 can be detected by measuring the inclination angle of the revolving structure 3 with the IMU sensor (revolving structure) 30S. Angle can be estimated.

<Lifting center calculation unit 930>
Based on the lifting angle θ calculated by the lifting angle calculating unit 920, the lifting center calculation unit 930 determines the center of the moving object 4 at which the lifting occurs, and determines the center of rotation when the moving object 4 is lifted. Compute Cr(Crb, Crf).

A method of calculating the floating center of rotation Cr will be described with reference to FIGS. 5 and 6. FIG. Assuming that the angle in the forward tilting direction of the revolving structure 3 is positive (+) as indicated by an arrow 55 in FIG. When tilting (when the front working device 2 side of the traveling body 4 floats up), it becomes a positive value, and as shown in FIG. becomes a negative value. Therefore, it can be determined whether the front work device 2 side or the counterweight 37 side of the running body 4 is floating depending on whether the lifting angle is positive or negative.

When the uplift angle θ is a positive value, the front working device 2 side of the traveling body 4 is lifted as shown in FIG. The contact line where 4 contacts the ground is defined as the rotation center Crb of the lift. On the contrary, when the lifting angle θ is a negative value, the counterweight 37 side of the traveling body 4 is lifted as shown in FIG. The line of contact where the traveling body 4 contacts the ground is defined as the center of rotation Crf of floating.

In this embodiment, as shown in FIGS. 4 to 6, the origin O of the vehicle body coordinate system is set at the intersection of the rotation axis of the boom 20 (the axis of rotation of the boom pin) and the operation plane of the front work device 2. The coordinates (a, c) of the positions of the rotation centers Crb and Crf with respect to the origin O on the operation plane of the front working device 2 are the relative angle φ and the dimensions of the revolving body 3 and the traveling body 4 (which can be stored in advance in the controller 34).

<Operation restriction area correction unit 730>
The operation restriction area correction unit 730 corrects the position of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system based on the positions of the rotation centers Crf and Crb when the traveling body 4 is lifted and the lifting angle θ. However, when the traveling body 4 is not lifted (when the lift angle .theta.=0), correction is not performed and the position of the boundary line 60 is output as the initial position. In addition, the operation restriction area correction unit 730 provides the position data of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system and the position data of each of the

front members

20, 21, 22 in the vehicle body coordinate system calculated by the posture calculation unit 710. , the shortest distance d between the boundary line 60 of the restricted operation area 59 and the front working device 2 is calculated.

A method for correcting the position of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system by the operation restriction area correction unit 730 will be described. Let P(X, Z) be an arbitrary point that constitutes the restricted operation area 59, and let Q(X', Z') be a point rotated by the floating angle θ around the rotation center Crf, Crb(a, c). The following formula (2) holds.

As already mentioned, θ, a, and c in the above formula (2) are calculable constants. Therefore, for example, a function Z′ =g(X') can be expressed as a function of X. Note that the conversion by equation (2) is performed by rotating the initial position (X, Z) of the boundary line 60 by -θ around the rotation centers Crf, Crf, and by the coordinates (a, c) of the rotation centers Crf, Crf. It moves in parallel.

<Operation command unit 310>
Based on the shortest distance d between the boundary line 60 of the operation restriction area 59 and the front work device 2 and the output of the operation sensor 33b, the operation command unit 310 controls the electromagnetic waves related to the boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A. An operation command value necessary for driving the control valve 35a is calculated. The shortest distance d is calculated based on the position (initial position or corrected position) of the boundary line 60 output from the restricted operation area correction unit 730 . That is, when the running body 4 is floating, the calculation is based on the corrected position of the boundary line 60, and when the bottom surface of the running body 4 is in surface contact with the ground, the calculation is based on the initial position of the boundary line 60. be done.

While the hydraulic excavator 1 is operating (or while the area restriction control is valid), the operation command unit 310 sets the shortest distance d between the boundary line 60 of the operation restriction area 59 and the front work device 2 to a predetermined value. It is determined whether or not it is smaller than (threshold). When the shortest distance d becomes smaller than the predetermined value, the operation command unit 310 controls the boom cylinder 20A, the arm cylinder 21A, and the bucket to stop the front working device 2 regardless of the output from the operation sensor 33b. Set the target operating speed of cylinder 22A to zero. Then, the operation command unit 310 generates an operation command value necessary for driving each electromagnetic control valve 35a according to the target operation speed, and outputs the generated operation command value to the corresponding electromagnetic control valve 35a, thereby The direction switching valve (control valve) 35b is driven. As a result, when the front working device 2 approaches the boundary line 60 , the front working device 2 is stopped, and the front working device 2 is prevented from entering the restricted operation area 59 .

When the shortest distance d is equal to or greater than a predetermined value, the target speeds of the boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A are calculated according to the output of the operation sensor 33b, and the front working device 2 is operated according to the operator's operation. Operate.

<Monitor 110>
An example of a screen on the monitor 110 showing the positional relationship between the boundary line 60 of the restricted operation area 59 and the hydraulic excavator (working machine) 1 is shown in FIG. When the running body 4 is not lifted, an image is displayed in which the bottom surface of the running body 4 and the ground are in full contact with each other, as shown in FIG. The value of the shortest distance d of the work device 2 is displayed. In the example of FIG. 7, the shortest distances da (+0.5 m) and db (+1.2 m) between the vertical boundary line 60a located in front of the hydraulic excavator 1 and the horizontal boundary line 60b located below the hydraulic excavator 1 are displayed respectively. When the traveling body 4 is lifted, an image of the traveling body 4 floating as shown in (b) on the right side of the drawing is displayed, and the boundary line 60 (60a, 60b) and the shortest distance d (da, db) of the front working device 2 are displayed.

By correcting the boundary line 60 according to the lifting angle θ described above, the position of the boundary line 60 on the screen of the monitor 110 is maintained even if the moving object 4 is lifted.

Although two shortest distances are displayed according to the shape of the boundary line 60 in the example of FIG. 7, only the distance between the front working device 2 and the nearest boundary line 60 may be displayed. In addition, the positional relationship between the boundary line 60 of the operation restriction area 59 and the hydraulic excavator 1 may be displayed by changing the color or figure. For example, in the example of FIG. 7, the image of the hydraulic excavator 1 is displayed, but instead of displaying this image, it is also possible to notify by a message or an alarm that the traveling body 4 is floating.

<Control procedure of the main controller>
FIG. 8 is a flow chart of processing executed by the main controller 34, explaining an example of the flow of calculation by each unit shown in the main controller 34 in FIG. In the following, each process (steps S110 to S210) may be described with each part in the main controller 34 shown in FIG. Further, detailed explanations of the processing of each part may be described in the description of each part. The relative angle φ between the traveling body 4 and the revolving body 3 is assumed to be zero degree.

First, in step S110, the attitude calculation unit 710 refers to the data detected by the

attitude sensors

30S, 20S, 21S, 22S, and 40S, and determines the attitudes of the boom 20, arm 21, bucket 22, traveling body 4, and revolving body 3. to calculate

In step S120, the operation restriction area calculation unit 720 determines the position of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system (initial position ).

In step S130, the floating determination unit 910 determines whether the running body 4 is in a floating state, based on whether there is an operation input to the travel control lever 33c and the output of the IMU sensor (rotating body) 30S. If it is determined that the traveling body 4 is floating, the process proceeds to step S140, and if it is determined that it is not floating, the process proceeds to step S200.

In step S140, the lifting angle calculation unit 920 calculates a change in the inclination angle (lifting angle) .theta. move on.

In step S160, the floating center calculation unit 930 determines in which direction the traveling object 4 is floating based on the floating angle θ calculated in step S140. is negative, the revolving body 3 is tilted forward and the counterweight 37 side of the running body 4 is floating (that is, the state of FIG. 6), so the process proceeds to step S170. On the other hand, if the rising angle is positive, the revolving body 3 is tilted backward, and the front working device 2 side of the traveling body 4 is floating (that is, the state of FIG. 5), so the process proceeds to step S180.

In step S170, the hydraulic excavator 1 is in the posture shown in FIG. The center of rotation Crf is set on the side (that is, the front side of the traveling body 4).

At step S180, the hydraulic excavator 1 is in the posture shown in FIG. (that is, the rear side of the traveling body 4) is set as the center of rotation Crb.

In step S190, the operation restriction area correction unit 730 determines the operation restriction area 59 in the vehicle body coordinate system based on the positions of the rotation centers Crf and Crb set in step S170 or S180 and the lifting angle θ calculated in step S140. The position of the boundary line 60 is corrected to be the corrected position. When the lifting angle θ is zero (when the traveling body 4 does not lift), the initial position is held as the position of the boundary line 60 .

In step S200, the boundary line 60 is displayed on the screen of the monitor 110 at the position corrected in step S190.

In step S210, the operation restriction area correction unit 730 obtains the position data of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system calculated in step S190 (initial position if there is no lifting, and Corrected position) and the attitude data of the

front members

20, 21, 22 calculated in step S110, the shortest distance d between the boundary line 60 of the operation restriction area 59 and the front working device 2 is calculated, and the operation is performed. Output to command unit 310 .

When the shortest distance d calculated by the operation restriction area correction unit 730 is smaller than a predetermined value (threshold value), the operation command unit 310 sets the target operating speeds of the boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A to zero. Then, an operation command value required for driving each electromagnetic control valve 35a is generated and output according to the target operation speed. As a result, when the front working device 2 approaches the boundary line 60, the front working device 2 is stopped. On the other hand, when the shortest distance d is equal to or greater than the predetermined value, the motion command unit 310 calculates the target speeds of the boom cylinder 20A, the arm cylinder 21A, and the bucket cylinder 22A according to the output of the operation sensor 33b. The front working device 2 operates accordingly.

<effect>
First, the subject of the present application will be explained again. For example, when a boundary line 60 as shown in FIG. The boundary line 60 on the vehicle body coordinate system also rotates and becomes different from the actual boundary line 60 . Therefore, it is conceivable to rotate the boundary line 60 around the origin of the vehicle body coordinate system by an amount that cancels the lifting angle θ, and then use the rotated boundary line 60 as a new boundary line 60 . However, as shown in FIG. 5, the actual floating of the running body 4 occurs centering on the point Crb located behind the running body 4 . In other words, it is not enough to rotate the boundary line 60 around the origin of the vehicle body coordinate system, and it is necessary to add a parallel displacement to the boundary line 60 according to the deviation between the origin of the vehicle body coordinate system and the actual rotation center Crb. . 5 and 6, the area denoted by reference numeral 69 is the limited operation area 69 corrected by adding only rotation about the origin of the vehicle body coordinate system.

Therefore, in the hydraulic excavator 1 of the present embodiment configured as described above, the main controller 34 calculates the lifting angle θ of the traveling structure 4 based on the output of the IMU sensor (revolving structure) 30S, and the lifting angle θ Based on this, the rotation center Cr (Crf, Crb) when the traveling body 4 is lifted is calculated, and the position of the boundary line 60 in the vehicle body coordinate system is corrected based on the lift angle θ and the rotation center Cr. As a result, the position of the boundary line 60 of the operation restriction area 59 in the vehicle body coordinate system is corrected according to the lifting angle θ of the traveling body 4 and the position of the rotation center Cr. (Area limit control) malfunction can be prevented.

5, 6, etc., when the relative angle between the revolving body 3 and the traveling body 4 is 0 degrees (the forward direction of the traveling body 4 and the direction in which the front working device 2 extends (the x-axis of the vehicle body coordinate system). direction) coincide with each other), the rotation center Cr of the traveling body 4 is aligned with the contact line Crf (FIG. 6) with the ground located on the side of the front working device 2 and the contact line Crf (FIG. 6) with the ground located on the side of the counterweight 37. line Crb (FIG. 5). Therefore, in the present embodiment, which of the two contact lines Crf and Crb is the center of rotation is determined by the sign of the floating angle θ. Specifically, when the lifting angle θ is negative, the revolving body 3 tilts forward and the contact line Crf becomes the center of rotation. . As a result, it is possible to accurately determine which of the front working device 2 side and the counterweight 37 side of the traveling body 4 is the center of rotation, so that the boundary line 60 can be corrected accurately.

In addition, in this embodiment, apart from determining whether or not lifting of the traveling body 4 has occurred, whether or not the lifting angle θ≠0 is established, the operation state of the traveling body 4 and the IMU sensor (turning body) 30S output state. Specifically, A) when the output of the IMU sensor (swivel body) 30S changes while the running body 4 is stopped, it is determined that floating has occurred and the position of the boundary line 60 is corrected; is running, or when the output of the IMU sensor (slewing body) 30S is constant, it is determined that no lifting has occurred, and the initial position is maintained without correcting the position of the boundary line 60. did. As a result, it is possible to accurately determine whether or not the traveling body 4 is lifted, so that the correction accuracy of the boundary line 60 can be improved.

Furthermore, whether or not the traveling body 4 has lifted can be determined by using the outputs of the two pressure sensors 20BP and 20RP that detect the rod side pressure and bottom side pressure of the boom cylinder 20A, respectively, as mentioned above. can be determined. That is, the main controller 34 calculates the thrust F1 of the boom cylinder 20A based on the outputs of the two pressure sensors 20BP and 20RP, When different and when the output of the IMU sensor (swivel body) 30S changes, correct the position of the boundary line 60 where it is determined that the lift has occurred, and B) when the calculated thrust force F1 matches the thrust force F2, or , when the output of the IMU sensor (revolving body) 30S is constant, it may be determined that no lifting has occurred, and the initial position may be maintained without correcting the position of the boundary line 60 . This method can also improve the correction accuracy of the boundary line 60 . However, this method is superior to the above-described method in that it can determine which of the two contact lines Crf and Crb is the center of rotation when the traveling body 4 floats. That is, if F1<F2 is established when floating occurs, it can be determined that the revolving structure 3 tilts backward and the contact line Crb becomes the center of rotation (see FIG. 5). Conversely, if F1>F2 is established , the revolving body 3 tilts forward and the contact line Crf becomes the center of rotation (see FIG. 6).

<Second embodiment>
Next, a second embodiment of the invention will be described. In the first embodiment, the relative angle φ between the revolving structure 3 and the traveling structure 4 was zero degrees. It is characterized in that the center of rotation Cr is changed accordingly. Note that the hardware configuration of the present embodiment is the same as that of the already described first embodiment, so description thereof will be omitted.

<Lifting center calculation unit 930>
FIG. 9 is a top view of the hydraulic excavator 1 according to this embodiment, and FIG. 10 is a side view of the hydraulic excavator 1 when the front working device 2 side of the traveling body 4 is lifted up in the cases of A and B of FIG. show.

As shown in FIGS. 9A and 9B, the running body 4 has different lengths in the front-rear direction (traveling direction of the running body 4) and in the left-right direction (perpendicular to the traveling direction). is longer in the front-rear direction than in the left-right direction. Therefore, the position of the rotation center Cr with respect to the origin O of the vehicle body coordinate system may vary depending on the relative angle φ between the revolving body 3 and the traveling body 4 . For example, as shown in FIGS. 10(a) and 10(b), even if the front work device 2 side of the traveling body 4 is in common, the rotation centers Crb and Crr of the two with respect to the origin O of the vehicle body coordinate system Positions (a,c) and (a',c') are different. Therefore, it is preferable to correct the position of the floating center of rotation Cr according to the relative angle φ between the revolving body 3 and the traveling body 4 .

In the case of FIG. 9A, a pair of left and right crawler belts 45 constituting the running body 4 contact the ground in front of the running body 4 (advance direction) and a contact line Crf where the crawler belts 45 contact the ground behind the running body 4 (backward direction). Either one of the two contact lines Crf and Crb with the contact line Crb that contacts the ground at can be the center of rotation. Both of the contact lines Crf and Crb are straight lines extending in the lateral direction of the traveling body 4 (perpendicular to the traveling direction).

In the case of FIG. 9B, the left crawler belt 45L of the pair of left and right crawler belts 45 constituting the traveling body 4 has a contact line Crl that contacts the ground at the edge extending in the longitudinal direction (advancing direction), and the right crawler belt 45R. Any one of the two contact lines Crl and Crr with the contact line Crr that contacts the ground at the edge extending in the front-rear direction can be the center of rotation. Both of the contact lines Crl and Crr are straight lines extending in the left-right direction of the traveling body 4 (perpendicular to the traveling direction).

Which of A and B in FIG. 9 corresponds is determined based on the relative angle φ between the revolving body 3 and the traveling body 4 detected by the revolving angle sensor 40S. FIG. 11 is a diagram showing which of A and B in FIG. 9 corresponds based on the relative angle φ. A point Cs in the drawing indicates the turning center of the turning body 3 . As shown in FIG. 11, the relative angle φ between the rotating body 3 and the traveling body 4 is assumed to be 0 degrees when the advancing direction of the traveling body 4 and the extending direction of the front working device 2 (the x-axis direction of the vehicle body coordinate system) are aligned. The sign of the relative angle φ is positive when the revolving body 3 turns to the right, and the sign is negative when it turns to the left.

In this embodiment, a threshold value is provided for the relative angle φ, and the position of the rotation center Cr of the traveling body 4 is classified based on the relationship between the threshold value and the relative angle φ detected by the turning angle sensor 40S. The thresholds for the relative angle φ are +45 degrees (-315 degrees), +135 degrees (-225 degrees), +225 degrees (-135 degrees), +315 degrees (-45 degrees), and two adjacent thresholds differ by 90 degrees. . A circle centered on the turning center Cs shown in FIG. 11 is divided into four areas A1, B1, A2, and B2 by these threshold values.

Area A1 (first area) has a range of relative angles φ from 0 degrees (−360 degrees) to +45 degrees (−315 degrees) and a range of relative angles φ from +315 degrees (−45 degrees) to +360 degrees (0 degree). The region B1 (second region) has a relative angle φ ranging from +45 degrees (−315 degrees) to +135 degrees (−225 degrees). In the area A2 (third area), the relative angle φ ranges from +135 degrees (-225 degrees) to +225 degrees (-135 degrees). Region B2 (fourth region) has a relative angle φ ranging from +225 degrees (−135 degrees) to +315 degrees (−45 degrees).

When the relative angle φ is in either the area A1 or the area A2, the floating center calculator 930 calculates one of the two contact lines Crf and Crb as the center of rotation. However, in the area A1, the contact line Crf becomes the center of rotation when the revolving body 3 tilts forward, and the contact line Crb becomes the center of rotation when the revolving body 3 tilts backward. On the other hand, in the area A2, the contact line Crb is the center of rotation when the revolving body 3 tilts forward, and the contact line Crf is the center of rotation when the revolving body 3 tilts backward.

When the relative angle φ is in either region B1 or region B2, the floating center calculation unit 930 calculates one of the two contact lines Crl and Crr as the center of rotation. However, in the region B1, the contact line Crl is the center of rotation when the revolving body 3 tilts forward, and the contact line Crr is the center of rotation when the revolving body 3 tilts backward. On the other hand, in the area B2, the contact line Crr is the center of rotation when the revolving body 3 tilts forward, and the contact line Crl is the center of rotation when the revolving body 3 tilts backward.

<Control procedure of the main controller>
FIG. 12 is a flowchart of processing executed by the main controller 34 according to this embodiment. The same reference numerals are assigned to the same processes as in FIG. 8, and the description thereof will be omitted, and the processes different from those in FIG. 8 will be described below.

At step S150, the floating center calculation unit 930 determines whether the running body 4 is in the front-back direction based on the relative angle φ of the running body 4 with respect to the revolving body 3. That is, it is determined whether the relative angle φ is included in either the area A1 or the area A2. If the relative angle φ is included in either the area A1 or the area A2, the process proceeds to step S160. On the contrary, if the relative angle φ is included in either the region B1 or the region B2 (that is, if the traveling body 4 is not in the front-rear direction (in the left-right direction)), the process proceeds to step 161 .

In step S160, the floating center calculation unit 930 determines in which direction the traveling object 4 is floating based on the floating angle θ calculated in step S140. is negative, the revolving body 3 is tilted forward and the counterweight 37 side of the running body 4 is floating, so the process proceeds to step S170. On the other hand, if the rising angle is positive, the revolving body 3 is tilted backward, and the front working device 2 side of the running body 4 is floating, so the process proceeds to step S180.

In step S170, since the revolving body 3 is tilted forward, the lifting center calculation section 930 is operated in the traveling direction (also referred to as the front-rear direction or length direction) of the traveling body 4 and on the side of the front working device 2 (that is, the traveling body). 4) to set the center of rotation. As a result, the rotation center Crf is set when the relative angle φ is included in the area A1, and the rotation center Crb is set when the relative angle φ is included in the area A2.

In step S180, since the revolving body 3 is tilted backward, the floating center calculation section 930 is operated in the traveling direction of the running body 4 (also referred to as the longitudinal direction or the length direction) and the counterweight 37 side (that is, the running body 4 ) to set the center of rotation. As a result, the rotation center Crb is set when the relative angle φ is included in the area A1, and the rotation center Crf is set when the relative angle φ is included in the area A2.

In step S161, the floating center calculation unit 930 determines in which direction the traveling body 4 is floating based on the floating angle θ calculated in step S140. is negative, the revolving body 3 is tilted forward and the counterweight 37 side of the traveling body 4 is floating, so the process proceeds to step S171. On the other hand, if the rising angle is positive, the revolving body 3 is tilted backward, and the front working device 2 side of the traveling body 4 is floating, so the process proceeds to step S181.

In step S171, since the revolving body 3 is tilted forward, the lifting center calculation unit 930 sets the center of rotation in the lateral direction of the traveling body 4 and on the side of the front working device 2 (that is, the front side of the traveling body 4). As a result, the rotation center Crl is set when the relative angle φ is included in the region B1, and the rotation center Crr is set when the relative angle φ is included in the region B2.

In step S181, since the revolving body 3 is tilted backward, the lifting center calculation unit 930 sets the center of rotation in the lateral direction of the running body 4 and on the side of the counterweight 37 (that is, the rear side of the running body 4). As a result, the rotation center Crr is set when the relative angle φ is included in the region B1, and the rotation center Crl is set when the relative angle φ is included in the region B2.

<effect>
According to the hydraulic excavator 1 configured as described above, the center of rotation of the traveling body 4 can be accurately calculated even when the relative angle φ between the revolving body 3 and the traveling body 4 is not zero. can improve the correction accuracy of

It should be noted that the present invention is not limited to the above-described embodiments, and includes various modifications within a scope that does not deviate from the gist of the present invention. For example, the present invention is not limited to those having all the configurations described in the above embodiments, but also includes those with some of the configurations omitted. Also, it is possible to add or replace part of the configuration according to one embodiment with the configuration according to another embodiment.

In addition, each configuration related to the controller 34 and the functions and execution processing of each configuration are implemented partially or entirely by hardware (for example, logic for executing each function is designed by an integrated circuit). can be Further, the configuration related to the controller 34 may be a program (software) that implements each function related to the configuration of the controller 34 by being read and executed by an arithmetic processing unit (for example, CPU). Information related to the program can be stored, for example, in a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), a recording medium (magnetic disk, optical disk, etc.), or the like.

In addition, in the description of each of the above embodiments, the control lines and information lines have been shown as necessary for the description of the embodiments, but not necessarily all the control lines and information lines related to the product does not necessarily indicate In reality, it can be considered that almost all configurations are interconnected.

DESCRIPTION OF SYMBOLS 1... Hydraulic excavator (working machine), 2... Front working device, 3... Revolving body, 4... Traveling body, 20... Boom, 20A... Boom cylinder, 20BP... Pressure sensor (boom bottom pressure sensor), 20RP... Pressure sensor ( boom rod pressure sensor), 20S...IMU sensor (third attitude sensor), 21...arm, 21A...arm cylinder, 21S...IMU sensor (third attitude sensor), 22...bucket, 22A...bucket cylinder, 22B...first Link member 22C...Second link member 22S...IMU sensor (third attitude sensor) 30S...IMU sensor (first attitude sensor) 31...Main frame 32...Driver's cab 33a...Operation lever 33b...Operation Sensor 33c Travel control lever 34 Main controller (control device) 35 Hydraulic control device 35a Electromagnetic control valve 35b Direction switching valve (control valve) 36a Engine (motor) 36b Hydraulic pump , 37... Counterweight, 38... Turning motor, 40... Track frame, 40S... Turning angle sensor (second attitude sensor), 41... Traveling motor, 45L... Crawler, 45R... Crawler, 59... Operation restricted area, 60 Boundary line 69 Operation restriction area 100 Operation restriction area setting device 110 Monitor (display device) 310 Motion command unit 710 Posture calculation unit 720 Operation restriction area calculation unit 730 Operation restriction Area correction unit 910 Determination unit 920 Angle calculation unit 930 Center calculation unit

Claims

a running body;
a revolving body rotatably attached to the upper part of the running body;
a work device attached to the revolving structure and comprising a plurality of front members;
a first attitude sensor that detects the attitude of the revolving body;
A working machine comprising a controller that stores the position of a boundary line of an operation-restricted area into which entry of the working device is prohibited on a vehicle body coordinate system set on the revolving structure,
The controller is
calculating the lifting angle of the traveling body based on the output of the first attitude sensor;
calculating a center of rotation when the traveling object is lifted based on the lift angle;
A working machine, wherein the position of the boundary line in the vehicle body coordinate system is corrected based on the lifting angle and the center of rotation.
The work machine of claim 1,
The controller is
when the lifting angle indicates the rearward inclination of the revolving body, a contact line at which the running body contacts the ground on the rear side of the revolving body is calculated as the center of rotation;
A working machine according to claim 1, wherein, when the uplift angle indicates a forward inclination of the revolving body, a contact line at which the running body contacts the ground on the front side of the revolving body is calculated as the center of rotation.
The working machine of claim 2,
further comprising a second attitude sensor for detecting the relative angle of the revolving body and the running body;
A working machine, wherein the controller calculates the center of rotation based on the relative angle.
The working machine of claim 3,
The controller is
When the relative angle is included in the range of 0 to 45 degrees, 135 to 225 degrees, or 315 to 360 degrees, the pair of crawler belts that make up the running body are positioned in front or rear thereof. Calculate the contact line that contacts the ground as the center of rotation,
When the relative angle is in the range of 45 degrees to 135 degrees or in the range of 225 degrees to 315 degrees, one of the pair of crawler belts contacts the ground at its longitudinally extending edge. A working machine characterized in that calculation is performed with the contact line as the center of rotation.
The work machine of claim 1,
The controller is
correcting the position of the boundary line in the vehicle body coordinate system when the output of the first attitude sensor changes while the traveling object is stopped;
A working machine, wherein the position of the boundary line in the vehicle body coordinate system is held when the traveling body is traveling or when the output of the first attitude sensor is constant.
The work machine of claim 1,
further comprising a plurality of pressure sensors for respectively detecting rod-side pressure and bottom-side pressure of a boom cylinder that drives the boom, which is one of the plurality of front members;
The controller is
calculating the thrust of the boom cylinder based on the outputs of the plurality of pressure sensors;
correcting the position of the boundary line in the vehicle body coordinate system when the thrust of the boom cylinder differs from the thrust required to support the work device and when the output of the first attitude sensor changes;
When the thrust of the boom cylinder matches the thrust required to support the work device, or when the output of the first attitude sensor is constant, the position of the boundary line in the vehicle body coordinate system is maintained. A working machine characterized by:
The work machine of claim 1,
further comprising a plurality of third orientation sensors that respectively detect the orientations of the plurality of front members;
The controller is
calculating the position of the working device in the vehicle body coordinate system based on the outputs of the plurality of third attitude sensors;
calculating a distance between the work device and the boundary line based on the corrected position of the boundary line in the vehicle body coordinate system and the position of the work device;
A working machine, wherein the working device is controlled so as to prevent the working device from entering the limited operation area based on the distance between the working device and the boundary line.